Automatic firearm with burst control means



AUTOMATIC FIREARM WITH BURST CONTROL MEANS Filed May 25, 1968 April 29, 1969 E. H. VERVIER Sheet HEX! April 1969 E. H. VERVIER 3,440,925

AUTOMATIC FIREARM WITH BURST CONTROL MEANS Filed May 23, 1968 Sheet 2 0f 2 Owen/rm BY g1 TJM United States Patent Ofiice 3,440,925 Patented Apr. 29, 1969 int. Cl. 1 41a 11/10 US. Cl. 89-129 11 Claims ABSTRACT OF THE DISCLOSURE A device is provided for limiting the maximum number of shots fired with each burst of an automatic firearm. The fire-control camshaft pivots a first rocking lever into a position in which teeth on the forward end of the first rocking lever cooperate with a tilting finger on the hammer and the rear end of the first rocking lever and a second rocking lever engage a lug on a catch for the hamrner to move the lug out of engagement with the hammer until the tilting finger on the hammer releases the teeth on the forward end of the first rocking lever, allowing the rear ends of the first rocking lever and the second rocking lever to pivot under spring action to the starting position thus releasing the lug for engagement with the ham- THEY.

The invention relates to an automatic firearm, comprising a pivoting hammer having an extension with stops engaging, in the armed position, in hooks provided on pivoting catches and a device making it possible to limit the maximum number of shots fired with each burst.

As known, an automatic firearm can be fired without interruption as long as the user depresses the trigger, until exhaustion of the magazine. With a firearm of this kind, the firing is interrupted only when the trigger is released or when the feed is interrupted.

While they enable the user to fire a rapid succession of shots, these firearms also suffer from the drawback of an excessive and sometimes even wasteful munitions consumption. Moreover, it may happen with these individual portable automatic firearms that, due to loss of self-control, the user wastes its munitions and empties the magazine of his firearm too fast and, in all probability, inopportunely, so that he may find himself with an empty magazine and thus disarmed, which may constitute a difficult or even dangerous situation.

In order to overcome these drawbacks, firearms have already been desinged which are fitted with devices for controlling the number of shots which may be fired by exerting a continuous pressure on the trigger. However, these control devices are permanently fitted into the fire arm, and consequently must be provided during assembly of the firearms concerned.

The object of the present invention is to remedy these disadvantages and relates to an automatic firearm with a burst control means, which is characterised therein, that the device for limiting the maximum number of shots fired with each burst comprises a first rocking lever which, by means of an arm pivoting under the action of a firecontrol camshaft, is brought into an operative position in which, during firing, its forward extremity cooperates with a finger which tilts said first rocking lever against the action of a return spring, while its rear end engages a lug on a catch which is thus moved away from the stop of the hammer and which thereafter pushes a lower shoulder of a second rocking lever, causing it to pivot in turn, so that the rear end is in turn brought into contact with said lug in order to prevent contact between said catch and the stop of the hammer until the aforesaid lug releases the forward extremity of said first rocking lever which then returns into its starting position under the action of the spring and simultaneously pushes back the second rocking lever into its starting position as well.

According to another feature of the invention, the first rocking lever, the second rocking lever, the pivot arm and the return spring of the first rocking lever are mounted into a removable casing lodged into the trigger-housing and having the form of an inverted U, one arm of which is provided with a fork at the front and with an aperture at the rear for allowing passage to the fire-control camshaft. The pivot arm has a tail subjected to the pressure of a protrusion of the firing lever and two pawls terminating in hooks, one of which engages underneath the first rocking lever having at the front end teeth meshing with the finger of the hammer and at the rear projections engaging with the lug of the catch, whilst the other bears on the second rocking level which also has projections at the rear.

The invention will now be explained with reference to the accompanying drawings, which illustrate the invention but in no restrictive sense.

FIG. 1 is a schematical side elevation of the limiting device lodged into the trigger'guard, and

FIG. 2 is an exploded view of the removable casing and of the parts contained therein.

The drawings show only those parts which are necessary for understanding the invention. Moreover, the complete functioning of the firearm will not be described. being well known.

The firearm concerned is an automatic rifle, fragmentarily illustrated, comprising in a known manner a triggerguard 1, on the lowcr portion of which is located a trig ger 2 mounted pivotably on an axle 3 against the action of a return spring 4. On this same axle 3 there Pivot further a forward catch 5 and a rear catch 6, provided with hooks 5a, 6a respectively, capable of engaging corresponding stops 9a, 9b of projection of the hammer 9 ivoting about the axle 10, because a spring 7 between said catches tends to tilt them to move their hooks 5n and 6a towards each other.

A fire-control camshaft 8, operated by an actuating button, here not visible, on a lateral face of the trigger housing, can be brought into a position determining the mode of firing, i.e. in addition to acting as a safety catch, it allows the weapon to be fired in single shots or in unlimited bursts as in a known firearm. Moreover, the control camshaft 8 also regulates the firing in controlled burst by acting on the device according to the invention, provided for limiting the maximum number of shots fired in each controlled burst. This device comprises in the trigger-housing a casing 11 having the general shape of an inverted U with a long arm 12 and a small arm 13. At the front, the long arm 12 has a fork 12a located on the axle 10 of the hammer 9, and at the rear an aperture 12b in which passes the fire control camshaft 8, so that the casing is held in position. Between the arms 12 and 13 is fixed an axle 14 on which are mounted side by side a first rocking lever 15, a second rocking lever 16 and a pivot arm 17. This pivot arm comprises a tail 17a whose extremity 17b can bear against the bottom of the trigger housing for limiting its movement, and further two pawls 17c and 17d, one extending forwards and in downward direction. the other rcarwards and in upward direction. The pawl 17c terminates in a hook 172 engaging underneath the forward end of the first lever 15. The pawl 17d terminates in a hook 17!: adapted to bear on a shoulder 16a located on the upper rear face of the second rocking lever 16 which also has a lower shoulder 16b located underneath the lower rear portion of the first rocking lever 15.

At the front, the first rocking lever has three teeth 15a, 15b and 156.

When the fire-control camshaft 8 is set for firing controlled bursts, a protrusion 8a of this camshaft bears on the tail 17a, in such a manner, that against the action of a return spring 18, the first rocking lever 15 pushed upwards by the hook 17e of pawl 17c tends to rotate in clockwise direction, in the same manner as the second rocking lever 16, whose upper shoulder 16a is subjected to the downward pressure of the hook 17h of pawl 17d. At this instant, the various pieces of the device each occupy the position illustrated in the drawing. The hammer 9 being then brought into the armed position shown in FIG. 1, its stop 9a is engaged by the hook a of catch 5. If at this instant a pressure is exerted on the trigger 2, the catch 5 pivots, the hook 5a disengages from the stop 9a and the hammer 9 thus freed is violently propelled towards the firing pin here not shown, by the action of a not illustrated spring. In the course of this movement the hammer 9 rotates on its axle 10 and entrains with it a finger 19. This finger, which is tiltably mounted on a pivot 20 fastened to the hub 9d, is subjected at its end 19a to the action of a spring 21 which tends to press its other end against a stop 9e of said hub. Entrained by the hammer 9, the end 19a meshes with the tooth a of the first rocking lever 15, which, against the action of the return spring 18, rotates in clockwise direction, so that a proiection 15d located on the rear portion of said rocking lever 15 comes into engagement with a lug 6b of catch 6, which is thus held in such a manner that its book 6a cannot engage the stop 9b of projection 9c of hammer 9. In this manner, when after the first shot the hammer 9 is pushed back towards the rearming position by the rearming system here not shown, it cannot be caught in this position because its stops 9a and 9b do not meet with any of the hooks 5a or 6a, so that the fire continues. During this rearming of the hammer, the finger 19 is brought back into its starting position, but this time underneath the second tooth 15b of the first rocking lever 15. Therefore, when the hammer 9 which was prevented from reengaging the books is again propelled forwards by its spring here not illustrated to fire the second shot, the finger 19 meshes with the tooth 15b. Consequently, the first rocking lever 15 pivots with greater force and a second projection 15e on the rear portion of this rocking lever 15 engages the lug 6b of catch 6, preventing the engagement of the hammer 9. After the second shot has been fired, the hammer 9 is pushed backwards and its stops 9a and 9b cannot engage with the hooks 5a or 6a, while the finger 19 is returned into its initial position, this time underneath the third tooth 150. When the hammer 9 starts its third forward movement to fire the third shot, its finger 19 engages the third tooth 15c of the first rocking lever 15 which again pivots in clockwise direction. In the course of this pivoting, the rear portion of rocking lever 15 bears on the lower shoulder 16b of the second rocking lever 16, whose rear segment 16c comes to be located in front of the lug 6b of catch 6, thus liberating the rear portion of rocking lever 15.

After the firing of the third shot, the hammer 9 returns towards the rear and its finger 19 disengages from the tooth 150, so that the first rocking lever 15 which has just been freed pivots under the action of its return spring 18 in counter-clockwise direction. Due to this pivoting, the rear upper portion of rocking lever 15 pushes upwards the shoulder 16a of the second rocking lever 16, which thereby pivots in the same direction as the rocking lever 15. In this manner, the rear segment 16c leaves the lug 6b and, under the action of the spring 7, the catch 6 returns in forward direction, so that its hook is again in the engaging position with the catch 9b of the hammer. Although the trigger 2 has not been released, the firing is thus automatically interrupted after the third shot. If for any reason the firing has been interrupted before the third shot, in particular owing to deliberate release of the trigger or because there are no more cartridges in the magazine or because of jamming, the release of the trigger 2 causes the catch to pivot rearwards and its lug 6b disengages from the projections of the first rocking lever 15, and the latter, under the action of its return spring 18, pivots in counter-clockwise direction to return into its starting position, so that the weapon is again ready to fire a burst of three shots.

The disclosed device could be adapted to fire a burst made up of a different number of shots, for example two, four or five.

What I claim is:

1. An automatic firearm having a trigger housing, a trigger, a pivoting hammer, an extension on said hammer, stops on said extension, two pivoting catches, books on said pivoting catches engaging with said stops in the armed position, by trigger action, a device for limiting the maximum number of shots fired with each burst, said device comprising a first rocking lever, 21 return spring acting on said first rocking lever, a pivoting arm and a fire-control camshaft which acts on said pivoting arm which in turn brings said first rocking lever into an operative position during firing, a finger controlled by said pivoting hammer and cooperating with the forward extremity of said first rocking lever which tilts against the action of said return spring, a lug on one of said two pivoting catches, the rear end of said first rocking lever engaging by said tilting said lug on said one catch which is thus moved away from one stop on said extension of said hammer, a second rocking lever, 21 lower shoulder on said second rocking lever which is pivoted in turn due to pushing action of the rear end of said first rocking lever on said lower shoulder, so that the rear end of said second rocking lever in turn engages said lug in order to prevent contact of said catch bearing said lug with said stop on said hammer until said lug releases said forward extremity of said first rocking lever which then returns into its starting position under the action of said return spring and simultaneously pushes back said second rocking lever into its starting position.

2. A firearm according to claim 1, characterised in that said first rocking lever, said second rocking lever, said pivot arm and said return of said first rocking lever are mounted into a removable casing lodged into said trigger housing.

3. A firearm according to claim 2, characterised in that said first rocking lever, said second rocking lever and said pivot arm are pivotably mounted on a common axle carried by said removable casing.

4. A firearm according to claim 3, characterised in that said removable casing is of inverted U-shape having two arms between which the axle is mounted.

5. A firearm according to claim 4, characterised in that one of said arms of said casing has at the front a fork bearing on the axle of the hammer and at the rear an aperture for passage of the fire control camshaft, which holds said casing in position.

6. A firearm according to claim 5, characterised in that said pivot arm has a tail subjected to the pressure of a protusion of said firing lever pivot and extends towards the rear and in downward direction to terminate in an edge adapted to bear on the bottom of the trigger-housing, and two pawls each terminating in a hook, one of which extends forwards so that its terminal hook engages underneath the forward portion of the first rocking lever, while the other pawl extends upwards and towards the rear to allow its terminal hook to bear on the rear upper face of the second rocking lever.

7. A firearm according to claim 1, characterised in that said first rocking lever has teeth at its forward portion, with which the finger carried by the hammer meshes successively, and in that the first rocking lever and the second rocking lever have projections on their respective rear portions which successively come into engagement with the lug of the catch.

8. A firearm according to claim 7, characterised in that the first rocking lever has three teeth at the front and two projections at the rear, whilst the second rocking lever has only one projection at the rear, which arrangement makes it possible to fire bursts of three shots.

9. A firearm according to claim 7, characterised therein, that in addition to a lower shoulder, said second rocking lever is provided on its upper face with a second shoulder bearing on the rear portion of the upper face of the first rocking lever and located below the terminal hook of the pawl of the pivot arm extending towards the rear and in upward direction.

10. A firearm according to claim 1, characterised in that the finger carried by the hammer is pivotably mounted on the hub of the hammer and is subjected to the action of a spring.

11. A firearm according to claim 1, characterised in that said return spring of the first rocking lever has the form References Cited UNITED STATES PATENTS 11/1961 Silsby 89-129 10/1967 Newcomb et al. 89129 BENJAMIN A. BORCHELT, Primary Examiner.

STEPHEN C. BENTLEY, Assistant Examiner.

US. Cl. X.R. 89191 

